Bra Size Calculator

Your Bra Size

How to Measure

  1. Band Size: Measure snugly around your ribcage, directly under your bust.
  2. Bust Size: Measure around the fullest part of your bust.

Bra Fit Measurement Guide

Find your perfect bra size at home using a soft measuring tape. You can measure in inches or centimeters—whichever you prefer.

Get Ready

Before you start, prepare these items:

A soft measuring tape

A mirror to check tape placement

A notepad or phone to record your numbers

Wear a snug top or lightly lined bra for better accuracy. Use a private, well-lit space with a mirror.

Tips for Best Results

Clothing: Choose fitted, non-padded, light clothing

Timing: Measure a few days after your cycle for the best accuracy

Mirror: Helps keep the tape straight and level

Step 1: Measure Your Band

Wrap the tape around your body, just under your bust. Make sure it’s level and snug (not tight).

Tip: Round to the nearest whole number.

Step 2: Measure Your Bust

Wrap the tape around the fullest part of your chest. It should be flat and not pressing into your skin.

Tip: Round up or down based on comfort.

Step 3: Calculate Your Size

Subtract your band number from your bust number.

The difference = your cup size.

Difference Cup Size

1 inch          A

2 inches     B

3 inches     C

4 inches     D

And so on

Example: Band = 34″, Bust = 36″ → 36 – 34 = 2 → Cup = B → Bra Size = 34B

Need help? Use our online calculator for quick results.

Cup Size Chart (Global Reference)

Difference in (cm) UK US EU FR AU
<1 AA AA AA AA AA
1 (2.5) A A A A A
2 (5.1) B B B B B
3 (7.6) C C C C C
4 (10.2) D D D D D
5 (12.7) DD DD/E E E DD
6 (15.2) E DDD/F F F E
7 (17.8) F DDDD/G G G F
8 (20.3) FF H H H G
9 (22.9) G I I I H
10 (25.4) GG J J J I
11 (27.9) H K K K J
12 (30.5) HH L L L K
13 (33.0) J M M M L
14 (35.6) JJ N N N M
15 (38.1) K O O O N
16 (40.6) KK P P P O
17 (43.2) L Q Q Q P
18 (45.7) M R R R LL

Note on Sizing Methods

Some brands add inches to the underbust to get your band size.
Example: 34″ underbust → 38″ band in traditional sizing.
Check which method your favorite brand uses.

Step 5: Try On and Adjust

Sizes may vary by brand. Try different styles for the best fit, support, and comfort.

Frequently Asked Questions

To get your bra size, you need two simple measurements:

  • Band Size – Measure around your ribcage, just under your bust. The tape should be snug but not tight.
  • Bust Size – Measure around the fullest part of your bust. Keep the tape level and comfortable.
  • Enter these numbers into the calculator, and it will show your correct bra size.

Yes! You can choose either inches or centimeters. The calculator will automatically convert the measurements for you.

Our tool uses official size charts from trusted bra brands. While it’s very accurate, comfort may vary depending on the style or fit, so consider it a helpful starting point for your decision.

Each brand has its size guide, which may result in slight variations. That’s why our calculator includes brand-specific suggestions for better fit.

We support a wide size range—from band sizes 27″ to 56″ (60–120 cm) and cup sizes A to Z—covering most standard and plus-size options.

The bust size options change based on your selected band size because they are directly related. That ensures better accuracy and easier selection.

We support popular brands like Victoria’s Secret, Marks & Spencer, Calvin Klein, Chantelle, and more. Our list keeps growing with time.

Absolutely. The calculator can convert your size for US, UK, EU, FR, AU, and JP sizing systems.

Yes, it works for most styles, including sports bras, T-shirt bras, balconettes, and more. However, for special bras (such as maternity or post-surgery bras), an extra fitting may be needed.

We don’t store personal data, but you can easily take a screenshot or write down your size for future reference.

Unlike basic calculators, we use brand-specific charts, offering more precise results based on each brand’s actual measurements.

Because a size like 34C can vary across brands, our tool ensures better fit by using data directly from the brands you love.

Yes! We’ve included charts from all major brands, so you’ll get size suggestions tailored to each one.

Yes, it supports brands from all over the world and provides size conversions tailored to your region.

Traditional sizing may not always align with the brand’s actual fit. Our tool combines your body measurements with brand data to provide more accurate results.

Not at all. Just take your new measurements and enter them. The calculator will provide you with a precise, accurate size.

Yes, in many cases. Our detailed brand charts and precise system provide results that are nearly as accurate as professional fittings—without the hassle.

Yes! Once you enter your details, you can see how your size may change across multiple brands instantly.